﻿// Copyright (c) 2011, Adaptiv Design
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
//     * Redistributions of source code must retain the above copyright notice, this
// list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation and/or
// other materials provided with the distribution.
//    * Neither the name of the <ORGANIZATION> nor the names of its contributors may
// be used to endorse or promote products derived from this software without specific
// prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
// IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
// INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
// NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.

using System;

namespace Alicanto.Lexing
{
    public partial struct Token
    {
        private const char DOUBLE_QUOTES = '\"';
        private const char SINGLE_QUOTE = '\'';
        private const char COMMENT = '#';
        private const char COLON = ':';

        #region Boolean
        public static readonly Token False = new Token("false", TokenType.Literal);
        public static readonly Token True = new Token("true", TokenType.Literal);
        #endregion

        public static readonly Token Null = new Token("null", TokenType.Literal);

        public object Constant()
        {
            if (Type == TokenType.Literal)
            {
                if (this == True) return true;
                if (this == False) return false;
                if (this == Null) return null;

                if (Str[0] == DOUBLE_QUOTES || Str[0] == SINGLE_QUOTE)
                {
                    return Str.Substring(1, Str.Length - 2);
                }
                else if (char.IsNumber(Str[0]))
                {
                    if (Str.Contains("."))
                        return Double.Parse(Str);
                    else
                        return Int32.Parse(Str);
                }
            }

            throw new Exception();
        }
    }
}
